A man has died three weeks after being critically burned in a suspicious house fire in north Queensland.
The 65-year-old man and a 47-year-old woman were rushed to hospital in a critical condition about 5.40am on August 9 after the fire at the home on Home Hill Rd in Ayr.
A second man aged in his 20s was taken to hospital in a stable condition.
The woman died that day but the older man was flown to the Royal Brisbane and Women's Hospital, where he died on Monday night.
Detectives are treating the woman's death as a murder.
Police say the woman and the older man had been in a relationship, with a domestic violence order in place since 2018.
Investigators from Ethical Standards Command will complete a report into the deaths for the coroner.
A mental health incident that saw police and emergency services called to the home hours before the fire is also under investigation.
The Ethical Standards Command and the Crime and Corruption Commission are reviewing the actions of police and ambulance officers, who left after speaking to all parties involved in the incident.
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